Electronic Control System Signature, ISX and QSX15 Engines – FAULT CODE 491

Wastegate Actuator Number 2 Circuit


Fault Code: 491
PID: S088
SPN: 1189
FMI: 3/3
LAMP: Yellow

High voltage detected at the wastegate actuator number 2 circuit when no voltage was being supplied by the electronic control module (ECM).

Engine will run derated.

Wastegate Actuator Number 2 Circuit

Circuit Description

The wastegate actuators are devices used by the ECM to control boost pressure.

Component Location

The wastegate controller is located on the air inlet horn. Actuator number 2 is the rear most solenoid on the controller.

Shop Talk

High voltage can be caused by a short circuit to battery or a short circuit to another wire in the harness.

Refer to Troubleshooting Fault Code t05-491.

Last Modified:  26-Oct-2010